Summary The Cessna 172M, registration C-GPUL, serial number 17275607, operated by Grondair, was chartered by the Quebec ministre des Ressources naturelles et de la Faune (Department of Natural Resources and Wildlife) for night aerial surveillance of poaching activities. The pilot and two wildlife protection officers were on board. At about 2145 eastern standard time, the aircraft took off from the Saint-Frdric aerodrome, Quebec, for a visual flight rules (VFR) flight. Shortly after take-off, due to foggy conditions, the chief of operations on board the aircraft redeployed the ground teams to an area more to the south of the surveillance area that was originally planned. The aircraft was reported missing at about 2300. It was found three days later in a wooded area 7nm southwest of the Saint-Georges aerodrome, Quebec. After striking the treetops, the aircraft crashed in an inverted position and caught fire. The three occupants sustained fatal injuries. Ce rapport est galement disponible en franais. Other Factual Information The pilot was certified and qualified for the flight in accordance with existing regulations. His pilot licence was issued in September2001. In February2002, he received an instrument rating and a night endorsement. In March2004, he received a Class1 instructor rating. The pilot was assistant chief instructor of the flying school operated by Grondair. He gave beginner lessons and instrument flight lessons on the Cessna172. The pilot had a total of 2560flying hours, including 378hours at night and 255instrument hours. According to the company, the pilot was a devoted and hard-working employee. The year before, he took part in night aerial surveillance of poaching activities. His work was highly respected by the regional manager of the Quebec ministre des Ressources naturelles et de la Faune (Department of Natural Resources and Wildlife), who specifically requested his services for anti-poaching operations. The pilot was described as being in good health and fit to fly, and he was not taking any prescription medication. The pilot's flight time and flight duty time log indicates that he had not exceeded the limits set by regulation. However, in accordance with the Canadian Aviation Regulations (CARs),1 the log does not record the time in which the pilot acts as an instructor. On 03November2005, the pilot flew a charter to Nmiscau, Quebec, where he spent the day of November4 on the ground. On 05 November 2005, the day of the accident, he started his duty time at 0836 eastern standard time2 and arrived at Saint-Frdric, Quebec, at 1216. He stayed at the aerodrome to do some office work, and got home around 1500 where he said that he was tired and that the scheduled night surveillance flight would be risky because of the fog. However, he did not voice these thoughts to his company. The pilot slept about one hour and left his home at about 1700 to go to the Saint-Frdric aerodrome, where he again did some office work for the flying school. The Atmospheric Environment Service does not maintain a weather station at the Saint-Frdric aerodrome. The Grondair offices are equipped with computers that pilots can use to request aviation weather reports. The pilot used weather information from Qubec, Mirabel, Sherbrooke and Saint-Hubert, Quebec, to plan the flight. At 1812, the pilot checked the terminal aerodrome forecasts (TAFs), aviation routine weather reports (METARs), graphic area forecasts (GFAs) and wind and temperature aloft forecasts (FDs) on the NAV CANADA website, which supplies weather information. None of these reports described the actual conditions on the planned route. Based on this information, the pilot-in-command determined that the conditions were favourable for VFR flight. At 1946, the pilot filed a flight plan with the Qubec flight information centre (FIC). Since he had already obtained weather information, he declined a weather briefing from the FICspecialist. Before boarding the aircraft, the pilot suggested the possibility of diverting to Sherbrooke or Montral because he thought that the prevailing fog might prevent him from returning to the Saint-Frdric aerodrome. Shortly before take-off, while the aircraft was at the Runway05 threshold, the pilot advised the company that he was taking off to see if the weather was favourable for the surveillance flight, and that he would come back and land if conditions were unfavourable. After take-off, a wildlife protection officer on board the aircraft redeployed the ground teams to an area more to the south of the surveillance area that was originally planned, because the weather conditions made it impossible to see ground references (see AppendixA). Several witnesses reported that, before the take-off time, the planned surveillance area was partly covered by fog. Persons who were near the crash site at the time of the accident reported that they heard an aircraft at low altitude but did not see it. They also saw fog in the vicinity. At about 2330, a Grondair Cessna172 en route to the Saint-Frdric aerodrome had to divert to the Saint-Georges aerodrome when 20miles south of its destination because the fog prevented the pilot from continuing the flight under VFR. At about 2340, the pilot flew over the Beauce VOR/DME (very high frequency omnidirectional radio range/distance measuring equipment) (VLV), then performed a VOR instrument approach to Runway06. Fog covered the ground between the VOR and the aerodrome. The pilot saw the runway lights from 3miles west of the aerodrome. A commercial pilot who was at the aerodrome a short time before the aircraft took off noticed haze and marginal visibility. The GFAs issued at 1241 and 1841 indicated that marginal VFRconditions3 were forecast for the area starting at1900. Occasional instrument flight rules(IFR) conditions4 were forecast, caused by ceilings of 800feet above ground level (agl) and a visibility of 2miles in rain showers. Fog was also forecast south of the St.Lawrence River valley. At 2200, according to the data recorded by automated stations, there was no difference between the air temperature and dew point at Beauceville, Quebec, and at Saint-Hilaire-de-Dorset, Quebec, which are located 12nm north and 11nm south, respectively, of the accident site. Fog forms when the temperature of the air falls below its dew point. The relevant area is covered by the Qubec radar. In this area, the radar floor, which is the minimum altitude at which an aircraft can be detected, varies depending on terrain features. The radar floor is approximately 1300 feet agl at the Saint-Frdric aerodrome and 3600feetagl in the Saint-Georges area. At 2149, a primary radar echo appeared 1nm east of the Saint-Frdric aerodrome; the radar target made a 180 turn to the right and then disappeared from the radar screen at 2154, at 5nm southwest of the aerodrome. No other relevant primary or secondary radar echoes5 were observed over the Saint-Frdric/Saint-Georges area during the flight period. It is therefore reasonable to believe that the aircraft took off at about 2148 and flew below the radar floor after the last primary radar echo was received. Since no secondary radar echoes were picked up at the same time as the primary echoes, it can be concluded that the aircraft's transponder wasnoton. The Cessna 172 is a single-engine high-wing model capable of carrying a pilot and three passengers. The aircraft was certified, equipped and maintained in accordance with existing regulations and approved procedures. Its last inspection was a 200-hour overhaul on 14October2005. At the time of the accident, the aircraft had no deferred maintenance items. Only the aircraft DME was unserviceable, and it had been placarded. The aircraft was equipped for night flight and forIFR. It was not equipped with an autopilot, a ground proximity warning system (GPWS) or a radio altimeter, nor was it required to be by regulations. There was no global positioning system (GPS) on board. In general, air operators are prohibited from using single-engine aircraft for an IFR flight or a VFR night flight with passengers. In this case, pursuant to the Subpart 702 (Aerial Work) of the CARs, Transport Canada had issued the company an operations specification authorizing it to carry passengers that perform essential duties related to the aerial work. To minimize the likelihood that the aircraft would be seen by poachers during an aerial surveillance operation designed to prevent illegal hunting, Transport Canada granted an exemption to Grondair, subject to certain conditions, allowing operation of the aircraft with its navigation lights switched off. Under this exemption, the pilot had to maintain an altitude of 1000feetagl, fly in VFR at all times, transmit his position on the appropriate frequency while in uncontrolled airspace, and keep the aircraft navigation lights on when not conducting an aerial surveillance operation. The aircraft was equipped with two VHF radios. No messages were received from the pilot by air traffic control (ATC) services. According to NAV CANADA, in order to communicate with the Qubec FIC, an aircraft must be about 1000feetagl over Saint-Frdric and 2500to 3000feetagl over Saint-Georges. At 2214, an open microphone was recorded for a few seconds on one of the following frequencies: 126.7MHz Qubec, 123.15MHz Parc des Laurentides and 126.7MHz Montral. The wildlife protection officers were equipped with two-way FM radios as part of the provincial government's new digital communications system. Although the messages were not recorded, the transmission times and the emitting station numbers were recorded in a computer file. However, since the Quebec ministre des Ressources naturelles et de la Faune did not yet have procedures for saving data in the event of an emergency, those data were overwritten before they could be saved. During the accident flight, the wildlife protection officer/navigator spoke with the ground teams a few times. Reportedly, the messages from the wildlife protection officers in the aircraft indicated that the fog prevented them from establishing their position with reference to the ground. No one in the aircraft used their cellular telephone during the flight. The flight was conducted in uncontrolled airspace, which means that ATC services were not provided. The Saint-Frdric and Saint-Georges aerodromes are uncontrolled facilities. This means that they do not provide ATC services for either ground traffic or local air traffic. Instrument approaches can be performed at these aerodromes, but the occurrence pilot did not have any instrument approach charts with him. The Saint-Georges aerodrome, located southwest of the town, has one runway (06/24) and its reference elevation is 893feet. The runway is equipped with low-intensity runway edge lights, threshold lights, runway end lights and with a typeJ aircraft radio control of aerodrome lighting (ARCAL) system. The ARCAL system allows the aerodrome lights to be switched on for approximately 15minutes from a range of 15nm. Runway24 also has a precision approach path indicator (PAPI), which usually can be seen from at least 4nm out. The Beauce VOR/DME is located 11nm from the runway and allows pilots to make non-precision instrument approaches. When getting close to the VOR, pilots follow a heading of 045M and may descend to the minimum descent altitude (MDA) of 1900feet above sea level (asl) or 1000feet agl without the DME. Pilots must not descend below the MDA if they do not have the required visual references. At the time of the accident, as indicated in the Canada Flight Supplement, the UNICOM station (private advisory service providing air-ground communications at uncontrolled aerodromes) at this aerodrome shut down at 1800 and there was no one at the aerodrome. As a result, the investigation did not determine whether the pilot activated the ARCAL system. The lowest IFR altitude for initiating an approach is 3550feet. After passing the BeauceVOR, the aircraft could descend to 1900feetasl. If the aircraft had a serviceableDME, at 8DME, the pilot could continue the descent to the MDA of 1500feetasl, but since the aircraft DME was unserviceable, the pilot had to maintain 1900feet until he established the required visual references at the Saint-Georges aerodrome or up to the missed approach point at 10DME from the BeauceVOR, expressed in minutes and seconds based on ground speed. On approach from the Beauce VOR, not many lights can be seen before the runway lights come into view. At that point, the town lights are in the background. The terrain overflown on approach is higher than the town, and the runway lights and the town lights are spread out over a greater distance crosswise of the approach path than lengthwise. In good visibility, the runway lights can be seen from above the accident site. At about 2300, the wildlife protection officer in charge of the ground teams advised Grondair that the aircraft had not been responding for almost an hour. When attempts to contact the aircraft were unsuccessful, Canada's search and rescue services were notified. The search and rescue operation was difficult because the aircraft's emergency locator transmitter (ELT) was not transmitting. Moreover, no distress calls had been received from the pilot or passengers. Since the last radio exchange between wildlife protection officers indicated that the aircraft was to proceed to Disrali, Quebec, the search focused on the area between the Saint-Frdric aerodrome and Disrali. The aircraft wreckage was found three days later. The aircraft crashed in a forest clearing 30miles east of the location where the wildlife protection officers in the aircraft were to rendezvous with those on the ground. The accident site is mile northwest of the 045radial for the VOR Runway06 approach of the Saint-Georges aerodrome, about 6nm southwest of the Saint-Georges aerodrome, and 5nm northeast of the Beauce VOR (VLV) (see Figure1). The accident site is at an elevation of 1350feet asl, some 500feet higher than the Saint-Georges aerodrome. The aircraft flew over a field before striking the treetops at the edge of the wood. The aircraft's initial trajectory in the trees was 067M. It entered the trees in cruise attitude. It started to break up on first contact with the trees and crashed in an inverted position in a clearing 372feet from the point of first contact. The wreckage was partly destroyed by fire. It was not possible to determine precisely when the fuel-fed fire started. However, examination of the wreckage revealed that there was no in-flight fire. Examination of the wreckage, systems and all components recovered revealed no faults that would have adversely affected control of the aircraft and no pre-impact failures or malfunctions. The engine was severely damaged by fire. The trees severed by the propeller and the impact marks on the leading edges of the blades indicate that the engine was functioning at the time of the crash. Examination of the flight controls could not establish the position of the flaps on impact. Examination of the seat-belts revealed that all occupants were buckled in. The buckles of the front seat shoulder harnesses were not attached to the seat-belt buckles. Several instruments were sent to the TSB Engineering Laboratory, but due to their condition, the readings at the time of impact could not be determined. However, the aircraft clock and the watch of one of the occupants indicated 2215. It could not be determined whether the navigation lights and instrument lighting were in use because no light bulbs were recovered. The cockpit and cabin were so damaged by the impact and post-crash fire that the occupants' space was reduced almost to nil. Although the three occupants were wearing their seat-belts, the accident was not survivable. The Dorne-Margolin model DM-6ELT was found in a severely burned condition in the aft fuselage of the aircraft. Only the circuit board and batteries were identified. No ELT signals were received. It was not determined if the ELT emitted a signal. At the time of the occurrence, Grondair was operating a fleet of about 25aircraft (models Cessna172, Cessna182, Cessna208, Cessna310, Piper Navajo and Beech King Air). The company had been conducting night aerial surveillance of poaching activities for about 15years. No other incidents or accidents associated with this type of operation have been reported to the TSB. The owner of Grondair is also the operations manager and chief pilot. Grondair uses a pilot self-dispatch system. The pilots are fully responsible for preparing, planning and conducting their flights. They are also required to ensure that their flight is conducted in accordance with the existing regulations and company procedures as published in the company operations manual. According to the company operations manual, the pilot is responsible for flight watch. The pilot is supported by the Grondair flight following system that shall monitor the progress of each flight from its commencement to its termination. In short, the flight follower was to be available by telephone. The pilot is required to advise the flight follower as soon as the itinerary or timetable is changed. On the day of the accident, following service was provided by the company manager, who was at the aerodrome before the take-off. He left before the aircraft departed but did not note the time, and no one was assigned to follow the flight on the aerodrome frequency. Night aerial surveillance of poaching activities consists of flying over a pre-determined area and looking for poachers. The wildlife protection officers on board the aircraft coordinate the movements of interception teams on the ground.6 The documentation issued by the Quebec ministre des Ressources naturelles et de la Faune does not specify a minimum flight altitude. However, according to information received, the pilot is asked to fly at 1000feetagl with the navigation lights off to avoid being seen by poachers. A response plan prepared by the local office of the ministre des Ressources naturelles et de la Faune details the duties of the airborne officers and ground teams, the equipment they need and the flight schedule. The plan does not set any meteorological limits or air operations criteria. The officer /navigator, who is seated in the aft cabin, is responsible for regularly advising the ground teams of the aircraft position. The ground teams received no position reports. In 2004, the Socit de la faune et des parcs (Wildlife and Parks Agency), since then replaced by the Quebec ministre des Ressources naturelles et de la Faune, published a revised version of the guide concerning the use of aircraft at the Socit de la faune et des parcs, mainly intended for personnel doing wildlife surveys. The primary purpose of this guide is to present the information required to ensure personnel safety. Although the Department recommends that the guide also be followed by employees involved in other air operations, the rules it contains are optional. Night aerial surveillance of poaching activities is not mentioned. As a result, no specific policies7 or standards more stringent than those prescribed in the CARs are provided for this type of operation. Officers from the local office of the Quebec ministre des Ressources naturelles et de la Faune had completed four night aerial surveillance operations of poaching activities before the accident, but no poachers were caught. The fifth operation (toile Filante operation) was scheduled for Friday and Saturday, 04and 05November2005, but the flight on 04November2005 was cancelled due to weather. A controlled flight into terrain (CFIT) accident occurs when an airworthy aircraft inadvertently strikes the terrain or water without the crew's suspecting the tragedy is about to happen. According to CFIT accident statistics collected by the TSB, the pilots had often tried to see the ground to fly VFR even though the flight was taking place in clouds, at night, in whiteout, or in other conditions that did not permit visual flight. More than half of such CFIT accidents occurred in VFR flight. Half of the VFR accidents in instrument flight conditions (IMC) occurred in mountainous or valley areas. It is clearly harder to avoid adverse weather and see unmarked obstructions at night. The pilot cannot spot obstructions as quickly or estimate distances as accurately. As a result, the pilot's ability to see and avoid obstructions is compromised. Section 602.115(b) of the CARs requires that flight visibility be at least 3miles on a VFR night flight in uncontrolled airspace. In addition, the distance of the aircraft from cloud must be at least 500feet vertically and 2000feet horizontally when the aircraft is operated at or above 1000feetagl; below 1000feetagl, the aircraft must be operated clear of cloud. Section 602.115(c)(ii) of the CARs requires that, except for take-offs and landings, aircraft on a VFR night flight must be operated at an altitude of at least 1000 feet above the highest obstruction located within 3miles horizontally of the planned route. The pilot on a VFR flight, when he is the only pilot on board, must fly, navigate by ground references, monitor the on-board systems and operate the radio. When visual references on the ground are obscured by adverse weather, the pilot must work harder. In some circumstances, the false horizon created by a sloping cloud base, rising terrain, oblique lights or protruding terrain features can disorient the pilot. About 10percent of all accidents in Canada occur during the hours of darkness, which is in line with the estimated percentage of all flights that take place at night (10percent also). However, almost 30percent of VFR accidents in IMC occur at night. Consequently, the number of this type of accidents that happen at night is proportionally very high. Black-hole illusion occurs when darkness, absence of visual cues and few lights distort the pilot's perception of altitude, attitude or both. When an aircraft is on approach to a runway and all is dark below the approach path with only the distant runway or airport lights providing visual stimulus, an illusory or false sense of height and/or attitude may be perceived. On a night approach in clear conditions over dark terrain, even experienced pilots can visually overestimate their altitude, which induces them to fly too low and touch down short of the runway. The problems associated with approaching in a black hole seem to be worse when the approach is long and straight-in and the aerodrome is right beside a small town and has sub standard runways and approach lights. The following TSB Engineering Laboratory report was completed: LP124/2005 - Instrument Examination. This report is available upon request from the Transportation Safety Board of Canada.